Question: Simplify to lowest terms. $\dfrac{22}{99}$
Answer: What is the greatest common factor (GCD) of 22 and 99? $22 = 2\cdot11$ $99 = 3\cdot3\cdot11$ $\mbox{GCD}(22, 99) = 11$ $\dfrac{22}{99} = \dfrac{2 \cdot 11}{ 9\cdot 11}$ $\hphantom{\dfrac{22}{99}} = \dfrac{2}{9} \cdot \dfrac{11}{11}$ $\hphantom{\dfrac{22}{99}} = \dfrac{2}{9} \cdot 1$ $\hphantom{\dfrac{22}{99}} = \dfrac{2}{9}$